Paspaliaris et al. 2021

The physical properties of local (U)LIRGs: A comparison with local early- and late-type galaxies

In this study, we modelled the spectral energy distributions (SEDs) of 67 local (ultra-) luminous infrared galaxies, U/LIRGs, using the CIGALE code, to calculate their physical properties. In order to pinpoint their place in the local Universe, we compared them with the SEDs of 268 early- and 542 late-type galaxies from the DustPedia archive.

U/LIRGs are the most massive and actively star-forming galaxies in the local Universe. We also provide the scaling relations that connect these physical properties.

One thing we can easily realise by visually inspecting the SEDs is that there is a big difference in the dust content (peak at ~100μm) among the three populations, with early-types being the most devoid and U/LIRGs the abundant ones.

By categorising U/LIRGs, due to their merging stage, we investigated how the physical properties depend on the phase of interaction of the parent galaxies.

In contrast to the local early- and late-type galaxies where old stars are the dominant source which warms up the dust, in U/LIRGs, the dust is mainly heated by the young stellar population. The corresponding fraction is higher for the late merging systems (M3, M4 classes) where young stars are responsible for the dust heating by more than 80%.

You can find more of this work at the corresponding paper published on the Astronomy & Astrophysics Journal:

Paspaliaris et al., A&A, 649 (2021) A137

This work was also presented at the 15th Conference of the Hellenic Astronomical Society, in July 2021.